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Climate change influences health through both direct and indirect impacts. In addition to dehydration, hyperthermia, and effects on cardiovascular, respiratory, endocrine, immune, and nervous systems, high temperatures are associated with increased rates of mortality, accidents at work, suicide, domestic violence, and assaults. Urban heat islands amplify the health effects of heat waves. Extreme climatic events lead to deaths and injuries. Climate change may also increase the development of skin cancers. More indirectly, climate change modifies the geographic distribution of some vector-borne diseases and aquatic bacteria (leading, for example, to cholera outbreaks). The melting of permafrost could generate viral and bacterial hazards. High temperatures and extreme climate events are associated with a decline in agricultural yields, which can lead to malnutrition and stunted growth. Climate change could exacerbate toxic algae bloom and has implications for allergies. It will also influence atmospheric concentrations of pollutants and increase the frequency of forest fires, and sand and dust storms, which are associated with respiratory problems. Rising sea levels may contribute to mass climate migration, leading to issues related to hygiene, infectious diseases, and conflicts. Groundwater salinization will affect access to drinking water. Ocean acidification will amplify the impact of tsunamis and hurricanes, and disrupt fishing-based economies. Measures to fight against and to adapt to climate change can also influence health. These measures focus on urban environments and the economic sectors of agriculture, transport, energy, and industry (as the largest emitters of greenhouse gases), all of which shape major determinants of health (including physical activity, diet, air pollution, noise, and chemical contaminants). The fight against climate change thus represents a tremendous opportunity to improve health. As such, it is important to incorporate public health issues into the research agenda related to climate change, in order to create an interdisciplinary continuum combining epidemiology and public health, climate sciences, the various human and social sciences, urbanism, and political science, among other disciplines.